There is known an egg counter for counting eggs which are conveyed on an egg collection conveyer to collect eggs laid by the poultry in a poultry house.
As shown FIG. 9, a conventional egg counter 30 comprises one infrared light emitting element array 31 and one infrared light receiving element array 32. The egg counter 30 is disposed above an egg collection conveyer 33.
Each of the infrared light emitting elements of said array 31 emits an infrared light R toward a predetermined area on the egg collection conveyer 33 where is substantially opposite to the infrared light receiving element array 32. When an egg E is passed through the predetermined area, the infrared light R emitted from the infrared light emitting element reflects on a surface of the egg E. Then the reflected infrared light R is received by the corresponding infrared light receiving element of said array 32, and a light intensity thereof is determined by a control means not shown in drawing. The control means is intended to detect a peak value of the light intensity of the infrared lights reflected on the egg E. The egg E is counted if the peak value is detected.